The present invention relates to a zoom lens system and, more particularly, to a small zoom lens system lending itself well fit for electronic still cameras or video cameras using solid-state image sensors as image pickup devices.
With recent rapid reductions in the weight and cost of video cameras, there is an increased demand toward reducing the size and weight of their lens systems.
So far, this object has been achieved by arranging second and third lens groups with a stop between them and moving the second and third lens groups in the directions to increase their magnifications, as typically set forth in Japanese Provisional Patent Publication No. Hei. 2-291515 which is directed to the same type of zoom lens system as described in the present disclosure.
However, the above conventional system uses as many as 11-12 lenses and so is still far from satisfactory in terms of the front lens diameter.